Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B64—AIRCRAFT; AVIATION; COSMONAUTICS
  • B64C—AEROPLANES; HELICOPTERS
  • B64C3/00—Wings
  • B64C3/30—Wings comprising inflatable structural components

Definitions

• the present invention relates to a pneumatic, i.e. Pressurized with compressed air and its shape can be changed through the targeted action of compressed air, so-called adaptive wings according to the preamble of patent claim 1.
• Various pneumatic wings per se have been proposed and are known, for example from two groups of documents: one group describes wing structures which are constructed from a large number of tubular elements: US 3,473,761, US 4,725,021 and US 3,957,232; the wing structures of the other group are kept in shape by spacer threads and textile webs (so-called "webs”): DE 949 920, US 2,886,265, US 3,106,373 and US 3,481,569.
• Pneumatic wings per se only fulfill a meaningful technical task if they offer advantages in terms of weight, manufacturing costs, simplicity of handling and flight characteristics compared to other, non-pneumatic construction methods and are also foldable when not in use; these advantages mentioned need not exist in all of the areas mentioned; an overall assessment should, however, make a pneumatic wing appear advantageous. Judging from the documents of the first group, a pneumatic wing according to US 3,473,761 appears heavy, complicated and expensive to manufacture and, what weighs the heaviest, is unsuitable for solving the static problems of a wing. In contrast to the aforementioned example, the wing according to US Pat. No. 3,957,232 is constructed from pressure pipes of large diameter.
• the proposed device is not suitable for generating the necessary circulatory or surface tension of the wing skin, or undergoes deformations that are not shown and mentioned. However, if one takes these deformations of the pressure pipes into account, one sees that the structure is heavy and, in the claimed construction, not very stable. In the third publication mentioned only one spar structure is built up from pneumatic elements; the rest of the wing gets its shape from battens.
• the wings or profiles which are known from the second group of documents are basically made up of the lower and upper skin and the threads or webs connecting the two elements.
• the solution known from US 3,106,373 differs from the others in that the whole wing envelope consists of an airtight spacer fabric that is bent and glued into the desired shape.
• the problem of this group is clearest from DE 949 920.
• the wing profile is symmetrical there.
• the lift (c A ) required for a wing - be it wing or rotor blade - can only be generated by the angle of attack.
• wing profiles shown in the other publications do not assume the shapes shown under pressure: in the area where threads or webs open into the wing skin, pressure and tension tensors act together and give the wing skin its final shape.
• the profile known from US 2,886,265, but to a certain extent also the others will essentially assume the form known from DE 949 920 with disappearing c A under pressure.
• a pneumatic wing is extremely poor for attaching control cables or rods, especially for moving the ailerons.
• the ailerons proposed in their entirety are modeled on those of rigid wing structures and do not represent technical progress.
• the object to be achieved by the present invention is on the one hand to create a pneumatic wing with a predetermined profile and a specific lift coefficient c A , with a pneumatic aileron attached while avoiding control cables or rods, on the other hand the wing profile as a whole or in part modified by the use of compressed air and optimized with regard to the flown speed, ie the usable speed range is increased overall.
• FIG. 1 shows a first section running essentially in the flow direction through a non-adaptive wing according to the invention without the rudder area
• Fig. 3 shows an essential step in the manufacture of the wing with a small change in the wing profile per unit length in the longitudinal axis
• FIG. 4 shows the method shown in FIG. 3 when the wing profile changes greatly per unit length in the longitudinal axis
• 9 shows a cross section through the trailing edge of the wing in an asymmetrical design
• 10 shows a detail of a variant of FIG. 7, 8 or 9.
• FIG. 12 shows a further variant for actuating the aileron
• FIG. 13 shows a variant of FIG. 2.
• FIG. 1 shows a section running in the direction of flow through an inventive but not adaptive wing.
• This has an airtight skin, divided into epidermis 1 and hypodermis 2.
• textile webs 3 which are made, for example, of woven material with a small stretch;
• fabrics made of aramid fibers are mentioned, although newer high-strength and low-stretch materials are now appearing on the market.
• the textile webs 3 are permeable to air and can even have holes for faster pressure equalization between the cells formed by them.
• individual webs 3 can be made airtight, so that any pressure loss does not affect the entire wing.
• the hollow body formed by the epidermis and hypodermis 1, 2 and textile webs 3 is flat when not inflated and can be easily folded or rolled. In the inflated state, it assumes the shape shown schematically by FIG. 1, the upper and lower skin 1, 2 of course bulging out between the webs 3, as described in more detail in relation to FIG. 5.
• the circulating or tensile stress ⁇ z of the epidermis and hypodermis 1, 2 is determined by the heights H of the webs 3, since for a
• FIG. 2 shows a measure according to the invention with which this fact can be countered: at a certain distance from the leading and trailing edges 4, 5 an airtight web 6, 7 is inserted, which allows the wing part that is in front of the web 6 lies and to set that behind the web 7 to a higher pressure ⁇ p 2 than the middle part of the wing, which is under the excess pressure ⁇ p x , as shown in FIG. 2.
• each cell defined by the webs 3 could have a own pressure are applied, which causes airtight webs 3.
• Fig. 3 is a first representation of the manufacturing process for determining the position and position of the webs 3.
• this ensures that the pressurized wing actually assumes the intended shape, but in the slack state, since the angle between web 3 and Enveloppe 8 in both points 10, 11 are the same.
• the force components resulting from the compressive and tensile stress tensor are essentially the same, both in the epidermis and hypodermis 1, 2, and in the web 10 under consideration. Due to the construction of the webs 3 described in FIG. 3, for each selected section through the Wing exactly determine the coordinates of the points of contact 10, 11, which are at the same time those of the intersections of the envelope 8 with the planes of the webs 3.
• the heights H of the webs 3 are also known.
• both the dimensions of the fabric webs used for the webs 3 and the positions of the lines along which the webs 3 are to be connected to the envelopes can be constructed. If an already airtight fabric is used for the envelope 8, the seam lines are then sealed with a plastic that bonds with the sealing plastic. If the envelope 8 is only to be sealed after the webs have been sewn, this is done, for example, according to known methods of plastic lamination of fabrics. According to the invention, welding can also take the place of a sewing connection.
• Either the textiles used can be welded directly; then the webs 3 are bent at their upper and lower edges, for example by approximately 90 °, and the strips thus formed are welded thermally or with ultrasound to the epidermis and hypodermis 1, 2. If, on the other hand, the textile materials cannot be welded directly, the above-mentioned strips, which have been formed by folding, can be laminated with plastic before folding and then welded to the already coated upper and lower skin 1, 2, for example, by one of the methods mentioned.
• a third variant according to the invention is not only to pretreat the webs 3 in the manner described, but also to provide the upper and lower skin 1, 2 with plastic strips and then to weld them to the strips of the webs 3. The entire envelope 8 is then sealed. Fig.
• a whole wing or only parts of it has a profile which can vary greatly in the longitudinal direction, the procedure described for Fig. 3 must be modified. If the desired wing profile is given, then, for example, 1 fastening lines 25 for the epidermis Textile webs 3 set according to the required bending stiffness of the flying ice. Then, nestling balls 26 are inserted, which touch the fastening line 25 and the subcutis 2 at the same time. The number of points of contact between the conforming spheres 26 and the subcutis 2 results in the fastening lines in the subcutis 2 which are numbered 27.
• FIG. 5 is a schematic representation of a cell 12, which extends essentially over the wing length L, and is formed by the epidermis and hypodermis 1, 2 and two adjacent webs 3. If the wing volume is pressurized, the domes and subcutaneous tissue 1, 2, as already said. These bulges have a circular arc shape of radius R, which is determined by the height H of the webs 3 and their spacing B.
• the height ⁇ H of the bulge is only of H and B, _ however not dependent on the pressure ⁇ p if ⁇ p>o; this is because both the pressure acting on the epidermis and hypodermis 1, 2 and the tensile stress tensor both depend linearly on the pressure ⁇ p.
• the tensile stresses acting in the webs 3 are decisive for the stability and load-bearing capacity of the flying ice. If a wing according to the invention is loaded by the generated buoyancy forces, these cause bending moments in the wing root, which essentially reduce the tensile stresses in the wing direction in the upper half of the webs 3, but increase in the lower half.
• FIG. 6 shows an advantageous embodiment of a web 3 in the longitudinal direction of the wing; the wing tip is to the left, the wing root to the right.
• the low-stretch fabric used is identified by the number 13 - used in such a way that the course of the thread is used on the one hand in the longitudinal direction and, on the other hand, perpendicular to it: The tensile stresses in the web 3 are thus directly caused by the horizontally and vertically acting ones Forces generated.
• the fabric 13 is now supplemented by a second, also low-stretch fabric 14, the thread course of which is rotated, for example, by 45 ° with respect to that of the first fabric 13.
• a cutout 20 in which the first tissue 13 behind it is made visible.
• Fig. 7 shows schematically the design of the trailing edge of an adaptive wing. From a cell, here numbered 15, both the epidermis 1 and the hypodermis 2 are each covered with a second, here 16, 17, upper and lower double skin. These are sewn to the epidermis and hypodermis 1, 2 each approximately in the middle of the width B of the cells 18 following the cell 15. This results in channels 19 of approximately the shape shown in FIG. 10 over the width of the aileron, it having to be taken into account that the height .DELTA.H of the bulges is shown greatly exaggerated. If the pressure in the cells 18 is of the size ⁇ p x , that in the channels 19 is essentially of the same size.
• the epidermis and hypodermis 1, 2 in the area of the cells 18 are deformed approximately in a straight zigzag and only the double skins 16, 17 have arcuate bulges. If the pressure .DELTA.p 2 in the ducts 19 located under the double skins 16, 17 is increased in such a way that .DELTA.p 2 > Ap lf the bulges of the double skin 16 or 17 increase, and on the upper skin stretched in a zigzag manner Curvatures in the direction of the cells 18.
• the channels 19 are thickened and - because of the small extensibility of the tissue used - shortened in the direction of flow, as a result of which the wing in the area of the cells 18 assumes the shape shown in FIG.
• the pressure ⁇ p 3 in the channels 19 on the underside of the wing can be reduced in such a way that ⁇ p 2 > ⁇ p 1 > ⁇ p 3 .
• This embodiment of the wing which is characterized on the basis of FIGS. 7, 8, can comprise only a part or the entire span of a wing. Likewise, the number of cells 18 affected by this design depends on the selected wing characteristic.
• the lower double skin 17 extends over more cells 18 than the upper double skin 16.
• the shape of the wing and thus the c ⁇ value can be changed over a larger area become.
• This also changes - just by modifying the trailing edge - the optimal speed range of the wing.
• FIG. 10 shows a variant of the described design of the channels 19; only one channel 19 is shown as a representative; the others are trained accordingly.
• a thin-walled hose 21 made of an elastomer is inserted in the channel 19, formed from the space between the outer skin 1 and the upper double skin 16. This hose is closed at its ends; For example, at the end lying against the wing root, the pressure hose 22 opens into the channel 19.
• pressure hoses 22 can be inserted into the elastic hose 21 at several points in order to accelerate the pressure change.
• pressure hoses 22 lead to the wings - specifically to the channels 19.
• the control can be effected conventionally, for example by means of a control stick and - in the case of variants according to FIG. 9 - by actuating a flap however, not a tensile force as with control cables, but a change in pressure in the channels 19.
• 11 a, b are the representations of an overall adaptive wing.
• the textile webs 3 - the number of which is shown in reduced form - each have a channel 28.
• These channels 28 are designed like the channels 19 according to FIGS. 7, 8, 9 or as pockets 29, each of which accommodates an elastomeric hose 21, as described in FIG. 10.
• the underside of the wing is designed as described for FIG. 9.
• 11 a the channels 19 on the underside of the wing are overpressure with respect to the inside of the wing, the channels 19 in the webs 3 are almost pressureless or only pressurized to such an extent that the webs 3 are not shortened.
• the pressure in the channels 19 in the webs 3 is now increased, the heights of the webs 3 decrease and the entire wing becomes flatter, as shown in FIG. 11b.
• the change in shape can be controlled both via the size of the channels 19 in the webs and via the pressure; in principle, each of these channels 19 can be subjected to an individual pressure. However, if only a single pressure is to be used, the size of the channels 19 is the only parameter for changing the height of the profile. Shortening the webs also changes the curvature of the wing. In order to compensate for an enlargement of the curvature, the channels 19 on the underside of the wing can now be relaxed. This makes the wing lower with controllable change of the curvature. The trailing edge is not shown in Fig.
• the wing is constructed from two initially separate parts, a wing 31 and an aileron 32.
• the two parts 31, 32 are connected - for example by welding or gluing - in the outermost regions of two cells 33, 34, but over the entire width of the Aileron 32.
• Cell 33 limits wing 31 to the rear
• cell 34 limits aileron to the front. Because of the static function of the wing 31, it can be assumed that the pressure in cell 33 is higher than in cell 34.
• the wing 31 and aileron 32 are connected by two flat actuators 35, 36, which are basically constructed and dimensioned in the same way.
• the structure of each actuator 35, 36 consists of a double skin 37, 38 with airtight channels 19, which are formed between longitudinal lines 39, along which the double skins 37, 38 are connected.
• both actuators 35, 36 are pressurized, so that an average shortening occurs.
• the aileron 32 is pulled toward the end of the wing 31 and, because of the pressure difference in the parts 31, 32, the indentation of the cell 34 is created.
• the pressure in the upper actuator 35 is increased and reduced in the lower actuator 36.
• Actuator 35 is thereby shortened, actuator 36 is lengthened, which results in the intended deflection of the aileron.
• the actuators 35, 36 are each connected to the wing 31 and the aileron 32 along a line and cause line-related forces.
• the actuators 35, 36 shown in FIG. 12 other actuators that generate line forces also perform the task.
• a variant of the exemplary embodiment according to FIG. 2 is shown in FIG. 13. 2 works with a predetermined pressure difference between leading and trailing edges, 4, 5 on the one hand and the intermediate part of the wing on the other. The curvature of the webs 6, 7 and thus also their tendons can be determined so that the wing assumes the predetermined shape. However, if the overpressure of the leading edge 4, the middle part of the wing and the trailing edge 5 is to remain variable, the variant shown in FIG. 13 is to be preferred.
• the airtight web 6 at the leading edge 4 is shown here.
• the construction for the trailing edge 5 is completely analog.
• the airtight web 6 is dimensioned such that it forms the part of the nestling circle 9 which is remote from the wing nose and is intended to form the separation of the leading edge 4 and the middle part of the wing.
• the airtight web 6 is then pierced by air-permeable webs 3.
• the web 6 is connected to the webs 3 at fastening points 24 by the same procedure as described for the connection of the webs 3 to the epidermis and hypodermis 1, 2.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Aviation & Aerospace Engineering (AREA)
• Toys (AREA)
• Aerodynamic Tests, Hydrodynamic Tests, Wind Tunnels, And Water Tanks (AREA)
• Feedback Control In General (AREA)
• Retarders (AREA)
• Tents Or Canopies (AREA)
• Laminated Bodies (AREA)
• Treatment Of Fiber Materials (AREA)
• Fluid-Damping Devices (AREA)
• Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
• Vibration Prevention Devices (AREA)
• Aiming, Guidance, Guns With A Light Source, Armor, Camouflage, And Targets (AREA)

Priority Applications (12)

Applications Claiming Priority (2)

Publications (1)

Family

ID=4218879

Family Applications (1)

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Cited By (12)

Families Citing this family (56)

Citations (13)

Family Cites Families (4)

• 1997
  • 1997-05-14 BR BR9702347-7A patent/BR9702347A/pt not_active IP Right Cessation
  • 1997-05-14 AU AU26309/97A patent/AU712971B2/en not_active Ceased
  • 1997-05-14 CZ CZ1998815A patent/CZ295332B6/cs not_active IP Right Cessation
  • 1997-05-14 CN CN97190912A patent/CN1080225C/zh not_active Expired - Fee Related
  • 1997-05-14 HU HU9901554A patent/HU222475B1/hu not_active IP Right Cessation
  • 1997-05-14 AT AT97917986T patent/ATE210042T1/de not_active IP Right Cessation
  • 1997-05-14 JP JP10506421A patent/JPH11512998A/ja not_active Ceased
  • 1997-05-14 IL IL12332997A patent/IL123329A/xx not_active IP Right Cessation
  • 1997-05-14 US US09/043,527 patent/US6199796B1/en not_active Expired - Lifetime
  • 1997-05-14 NZ NZ329761A patent/NZ329761A/xx unknown
  • 1997-05-14 EP EP97917986A patent/EP0851829B1/de not_active Expired - Lifetime
  • 1997-05-14 WO PCT/CH1997/000190 patent/WO1998003398A1/de active IP Right Grant
  • 1997-05-14 CA CA002232321A patent/CA2232321C/en not_active Expired - Fee Related
  • 1997-05-14 DE DE59705660T patent/DE59705660D1/de not_active Expired - Lifetime
  • 1997-05-14 ES ES97917986T patent/ES2165044T3/es not_active Expired - Lifetime
  • 1997-05-14 PL PL97326030A patent/PL183614B1/pl not_active IP Right Cessation
• 1998
  • 1998-03-09 MX MX9801856A patent/MX9801856A/es unknown

Patent Citations (13)

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